LibreSSL ocspcheck through 4.4.0 Memory Exhaustion via Unbounded OCSP HTTP Response
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fix or patch referenced
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
LibreSSL's ocspcheck utility, used to check certificate revocation status via OCSP, can be made to run out of memory by a malicious OCSP responder or an attacker intercepting plain HTTP traffic, which sends endless HTTP headers or body data. The result is a denial of service, because certificate status checks fail or cannot complete.
Summarized by anthropic/claude-haiku-5.5. Verify details against the original sources.
Read the original description
LibreSSL ocspcheck through 4.4.0 contains a memory exhaustion vulnerability that allows malicious OCSP responders to exhaust memory by sending unbounded HTTP responses. Attackers controlling the responder or intercepting plain HTTP AIA OCSP traffic can stream endless headers or body data to http_head_read() and http_body_read(), denying certificate status checks.
Timeline
- CVE published
- First seen by cve.now
Affected versions
- OpenBSD LibreSSL
through 4.4.0